I will be getting a lightgun soon.
I'm not 100% certain which brand to get ATM, I need to spend a bit more time reading what I can about the various options, I think I will end up going for an Arcade Gun's ready made one though - with a black trigger!
To repeat an earlier posters question however, are there any plans to include force feedback? If you are, I may wait in till this has been done... I think it'll make playing much more fun!